Prenatally, CNMs may present with polyhydramnios due to impaired swallowing.6,11,19,23,24,29 Elevated maternal alpha-fetoprotein levels may also be present.10,11,17,30 Ultrasound may detect these lesions.12,23 When a suspicion is raised from an ultrasound, a fetal MRI is highly recommended.6,22. The gene discussed is AFP; the disease is Polyhydramnios.